I am getting this error since a while. This is the trace of the error;
Using Jenkins 2.190.3
Plugin version 1.4.1
I have setupped an access token on gitlab.com and using it as username/password credentials. And I also tried ssh key credentials, but that didn't work either.
It worked before.
I had the same issue , I just changed the API version user by gitlab in the settings. *API level v3*
It is working now
!Screenshot from 2021-01-19 15-07-14.png! ]